Field of the Invention
The invention relates to a conductor arrangement for producing an electromagnetic field and thereby transferring energy to vehicles driving on a surface of a route, in particular a route for road automobiles. The invention also relates to a route comprising the conductor arrangement, a method of building the conductor arrangement and a method of building the route. The vehicle can be, for example, a road automobile having wheels which can be steered by a driver of the vehicle. However, it is also possible that a track-bound vehicle travels on the route, such as a rail vehicle driving on rails which are embedded in the route.
Description of Related Art
While travelling on a route vehicles require energy for driving (i.e. propulsion) and for auxiliary equipment which does not produce propulsion of the vehicle. Such auxiliary equipment includes, for example, lighting systems, heating and/or air-conditioning systems, ventilation and passenger information systems. Not only track-bound vehicles (such as trams), but also road automobiles can be operated using electric energy. If continuous electric contact between the travelling vehicle and an electric rail or wire along the route is not desired, electric energy can be either withdrawn from an on-board energy storage or can be received by induction from an arrangement of electric lines of the route.
The transfer of electric energy to the vehicle by induction forms a background of the invention. The route side (primary side) conductor arrangement produces an electromagnetic field. The field is received by a coil (secondary side) on board of the vehicle so that the field produces an electric voltage by induction. The transferred energy may be used for propulsion of the vehicle and/or for other purposes such as providing the auxiliary equipment of the vehicle with energy.
Generally speaking, the vehicle may be, for example, a vehicle having an electrically operated drive motor. However, the vehicle may also be a vehicle having a hybrid drive system, e.g. a system which can be operated by electric energy or by other energy, such as energy provided using fuel (e.g. natural gas, diesel fuel, petrol or hydrogen).
WO 95/30556 A2 describes a system wherein electric vehicles are supplied with energy from the roadway. The all-electric vehicle has one or more on-board energy storage elements or devices that can be rapidly charged or supplied with energy obtained from an electrical current, for example a network of electromechanical batteries. The energy storage elements may be charged while the vehicle is in operation. The charging occurs through a network of power coupling elements, e.g. coils, embedded in the track. Induction coils are located at passenger stops in order to increase passenger safety.
In contrast, the focus of the present invention is to continuously transfer energy to the vehicle while it travels on the route. WO 2010/031596 A2 discloses a shaped block for positioning and/or holding a plurality of line sections of one or more electric lines along a driving way of a vehicle, wherein the shaped block has a plurality of recesses and/or projections, wherein the edges of the recesses and/or projections for the line sections in each case form the boundary of a space, into which one of the line sections can be brought, so that it extends in a longitudinal direction of the space, and wherein the longitudinal directions of the spaces, delimited by the edges of the recesses and/or by the projections, extend essentially parallel to one another in a common plane.
If an alternating electric current flows through the electric lines, an electromagnetic field is produced that induces an electric current in a receiver of a vehicle which is travelling on the driving way. The shaped blocks facilitate the laying of the electric lines in the driving way. WO 2010/031596 A2 discloses ways of integrating the shaped blocks in railways for rail vehicles. For example, the shaped blocks are placed in between the rails, the electric lines are laid into the spaces defined by the blocks and the blocks are covered by lids.
U.S. Pat. No. 4,836,344 discloses an electrical modular roadway system adapted for transmitting power to vehicles and controlling inductively coupled vehicles travelling thereon. The system comprises a plurality of elongated, electrically connected inductor modules arranged in an aligned end to end spaced apart order to form a continuous vehicle path. Each module has a magnetic core and power windings which generate a magnetic field extending above the road surface. The modules are embedded in the ground so as to be flush with the roadway surface over which a vehicle can travel. Each module is an elongated structure of uniform width and thickness so that they can be easily fabricated in quantity and readily installed in a roadbed with a minimum of labor and equipment. Each module comprises an iron core around which is wrapped a power winding comprising a series of coils.
The arrangement of these modules has disadvantages with respect to a reduced robustness and increased effort for building and maintenance of the roadway. Although the modules are pre-fabricated before they are laid on the route, electric connections between consecutive modules need to be assembled on site. Therefore, dirt and water may cause corrosion and cracks, especially in winter and enhanced by vibrations which always happen while vehicles travelling on the route.
As mentioned above, the shaped block or the inductor modules facilitate arranging the electric lines in the desired manner. The blocks or modules can be pre-fabricated. However, the blocks or modules are comparatively heavy. Furthermore, the electric line or lines should be protected against at least some of the substances which are typically used during construction of routes for vehicles.